Thomas m



T.' M. TELL.

(N6 Model.)

PURNAGB.

Patented Nov.. 13.1833.-

avewtaz" Umre- STATES PATENT Grinch.

rrHOMAs M. FELL, `or BROOKLYN, NEW YORK.

FURNACE.

SPECIFICATION forming,1 part of Letters Patent No. 288,416, dated November' 13, 1883.

Application flled June 114, 1883. (No model.) l

y vented an Improvement in Furnaces, of which the following is a specification.

My invention relates to the construction of the fire-boxes of locomotive engines and furnaces in which the fuel is fed to an auxiliary l or front gas-furnace, delivering into a second or back combustion-fumare@ the whole arranged and Operated as one furnace; and the object of my invention is economy of fueloombustion and the prevention of smoke. I attain these objects by the mechanism illustrated in the accompanying drawings, in

Which- Figure 1 is a vertical longitudinal section of all the parts; Fig. 2, a vertical cross-section of the front gasChamber, and Fig. 3 a general plan.

Similar letters refer to similar parts throughout the several views.

A represents the front of auxiliary gas-furnace, B the combustion or back furnace, and C the boiler and tubes; a and a Z, the usual water-Ways; b, the ash-pit, having an air-door, 0;. d, the grate-bars, and e drop-bars; f, cleaning-door; g, a casing of iron surrounding the front or auxiliary gas-furnace, A, and having an opening or stoking door, h, across the width of the grate-bars. This outer casing is bolted or fastened to the front water-Way, a, (see Fig. 3,) and is arranged to hold or receive a lining of fire-brick, c', or other heat-resisting material on the front and both sides.

k represents the fuel-charging door or doors, having a number of fine holes Vfor the admission of air, and which may be operated by a chain and pulley, as shown; m, aportablefreback, extending horizontally across the entire width of the furnace and down and under the front wall or water-way, ce, constructed with a number of ne holes, as seenin Figs. l and 3, for the purpose of delivering streams of hot air above the fuel and into the rear combustion-chamber, B. rIhis fire-back, which I prefer made of what is known as iron-stone, or of extra hard'iron, is supported by the side brick wall or lining, and when worn out can be easily removed and replaced by another `back through the doors k.

n represents a line of small air-pipes entering through the water-Way a Z, and 0 an extension-plate to facilitate stoking.

It will 1be noticed (Fig. l) that in order to operate this double arrangementof furnace from the front, and especially for stoking purposes through the door h, that the lower part of theusual water leg or way, a, is much shortened, as seen by the dotted lines, and that the usual feed-door is dispensed with. The entire depth of both A and B need not exceed the usual or present dimensions of locomotive nre-boxes.

The operation is as follows: The front chamber, A, is fed with fuel throughthe door 7c, and

which should be kept charged above the space or distance between the grate-bars and the bottom of m. Air entering by the bars and the perforations on the door k produces the lower or first combustion of thefuel, (carbonicoxide gas, &c.,) and on passing through the fuel or down and around to the combustion-chamber B, and being highly, heated, is ignited `by the fresh supply of fine jets of air entering by the back m and the pipes n, and thereby producing the second or the higher combustion of the fuel-gases. Soft coal burned in this furnace is kept in the chamber A until Well coked, and in this condition is stoked back so as to cover the bars under thcchamber B, Vand fresh fuel charged, as before stated. By keeping a thick bed of coal in the auxiliary or front chamber, A, and a thin and bright fire in B, the most economical effect can be producedfrom anykind of fuel Without smoke or the escape of combustible gas.

As modications of my invention, the surrounding spaces occupied by the fire material may be constructed to hold water; or such sides may be made part of the main shell of the boileryand the perforations on the door k may be temporarily closed by an outer door or plate, as seen in Fig. 2; but

What I claim as my invention, and desire to secure in this application, isfl. In a locomotive flre-box or furnace having a front fuel-chamber, A, and a rear com- IOO buSbiOnchambeF, B, the grate-bars d, extend- Vstructed as described, in combination with a 1o ing under botl'i'saidharnbers, injcombinapi'on front fuelchamber, A,Y a; rear.. Acombustionwith Jche feed 'and 'air door 7c, thelower'or stclchamber, B, 2i 'feedld0or, 7c, a Stokingldoor, h, ing door, h, and a lire-back, m, delivering,1 and grate-bars d, all arranged and operating streams of hot air into Iche rear combustionsubstantially as described.

chamber, B, all arranged and operating in the THOMAS MARA FELL. manner and for the purposes substantially de-Y Witnesses: l w f scribed. G. F. WELLMAN,

2. In furnaces, theportable [ire-backm, c0n-`y R. BALDWIN. 

